linux-kernel - Re: [PATCH 1/1] perf,tools: error out unsupported group leader immediately for perf stat

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150611140335.GB2696@kernel.org>
Date:	Thu, 11 Jun 2015 11:03:35 -0300
From:	Arnaldo Carvalho de Melo <acme@...nel.org>
To:	kan.liang@...el.com
Cc:	linux-kernel@...r.kernel.org, andi@...stfloor.org
Subject: Re: [PATCH 1/1] perf,tools: error out unsupported group leader
 immediately for perf stat

Em Thu, Jun 11, 2015 at 02:32:40AM -0400, kan.liang@...el.com escreveu:
> perf stat ignores the unsupported event and continue to count supported
> event. But if the unsupported event is group leader, perf tool will
> crash. After applying this patch, the unsupported group leader will
> error out immediately.

> Without this patch:
> $ perf stat -x, -e '{node-prefetch-refs,cycles}' --  sleep 1
> perf: util/evsel.c:1009: get_group_fd: Assertion `!(fd == -1)' failed.
> Aborted (core dumped)

> With this patch:
> $ perf stat -x, -e '{node-prefetch-refs,cycles}' --  sleep 1
> Error:
> The node-prefetch-refs event is not supported.

I get something different, maybe I am missing a patch?

With this patch:

  [acme@zoo linux]$ perf stat -x, -e '{node-prefetch-refs,cycles}' -- sleep 1
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument)
  for event (node-prefetch-refs).
  /bin/dmesg may provide additional information.
  No CONFIG_PERF_EVENTS=y kernel support configured?
  [acme@zoo linux]$ 

Applying it anyway, as it avoids a core dump and the message, albeit not
optimal, points to a problem with that event.

Have you tried this with other tools, like perf record?

- Arnaldo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/